For the purposes of this list, a "Judoon story" is one in which one living, authentic Judoon plays a part within the confines of the story, outside of flashbacks to previous stories and cliffhangers that lead into the following story. For this reason, stories such as The Timeless Children are absent due to the Judoons' only contribution being references to past Judoon stories. Stories like The End of Time, The Pandorica Opens and A Good Man Goes to War are also not included due to the Judoons' cameos being of no consequence to the plot of the story.
For the purposes of this list, a "Quark story" is one in which one living, authentic Quark plays a part within the confines of the story, outside of flashbacks to previous stories and cliffhangers that lead into the following story.
According to one account, the Master had the appearance of Roger Delgado while on Gallifrey. According to another, he had Anthony Ainley's likeness. According to another one, the one with James Dreyfus's appearance was the incarnation who ran away from Gallifrey.
While fighting to extend his life at the end of his regeneration cycle, many bodies were possessed by the Beevers incarnation, but all kept somehow reverting to his real being until he finally regenerated into the MacQueen one. Hence, these sections cannot be strictly chronological
For the purposes of this list, an "Ood story" is one in which one living, authentic Ood plays a part within the confines of the story, outside of flashbacks to previous stories and cliffhangers that lead into the following story. For this reason, stories such as The Waters of Mars are not counted due to the Oods' appearance being defined by their importance to following stories. Stories like Face the Raven, Hell Bent and Revolution of the Daleks are also not included due to the Oods' cameos being of no consequence to the plot of the story.
